What is the one thing financial analysts and traders do really, really well? It’s obvious. Excel. Not in the sense of excelling at, you know, stock-picking, for example, more’s the pity. Excel in the sense of Microsoft Excel.

There’s a very funny Twitter comedian, Alexis Gay, who operates under the handle @yayalexisgay. She does a great skit as the pretend girlfriend of a financial analyst/trader, although she doesn’t know what he spends his day actually doing. “They pay him an amount of money that sounds fake … but it’s real. One time, they took some of it back! That was crazy.”

What she does know is two things: First, he has “so many monitors”. Even worse, “one’s vertical”, she says. “He just takes data from the Bloomberg terminal and puts it into Microsoft Excel, and I’m like, now you are just making up reasons to have so many screens”. Second, she concludes, “The man really crushes Excel, and not just Vlookup”.

And I’m afraid, this is how people see those operating in the financial sector: a little bit obsessed by spreadsheets. Personally, I have a sneaking admiration for people who are really good at spreadsheets. It’s one of the great, unacknowledged tools of the modern era. Business plan showing a loss instead of a profit? Easy, peasy. Increase the number in cell DM14. Voilà! Profit.

Spreadsheet analysis can be applied to so many different things. Just on cue, Brad Preston, the CIO of Mergence Investment Managers, has done some spreadsheet analyses on the topic everyone actually wants to know about: the rugby.

Really, HT to Preston, the analysis is fabulous fun. What he investigates, among other things, is how well the official IRB rankings predict match outcomes. “This is a question we continually ask ourselves as investment professionals when considering any feature, metric, or factor of a security: does it actually predict forward-looking investment returns?”

This is another way of asking, who is most likely to win this weekend? And that’s because at the moment Ireland are at the top of the IRB ranking, closely followed by you-know-who. 

Read more: Ireland’s quarterfinal curse hovers over win against Springboks

So, he gathered the data from the IRB world rankings — get this — on a weekly basis over the past five years. Really, some people have too much time on their hands. Anyway, he compared the rankings of the two teams before the match to the resulting score margin.

Unsurprisingly, there is a strong positive correlation. However, it’s not quite as strong as you might expect, or at least I would have expected. Taking only the relative IRB rankings and home ground advantage into account, the comparison predicted the match outcome correctly 70% of the time, Preston found.

For games where the difference in ranking points between the teams was more than five, accuracy went up to 80%. “So, using the official rankings is probably a good strategy to use in your office Superbru pool, but probably not accurate enough to consistently beat the bookies.”

Speaking of the bookies, it’s interesting that the odds on the weekend’s game between Ireland and SA had put the Springboks slightly ahead, but by a pretty small margin as of the eve of the match. The margin was 52.38% in favour of the Springboks and 45.45% in favour of Ireland. And look how that turned out!

Those were much closer odds than the IRB ranking would project, not to mention, the wrong way around. And doesn’t that just tell you something, not only about rugby but about investing? As they are continually telling us, past performance is no guarantee of future results.

At least, we here in SA hope so. DM